An electronic smoking device, such as an electronic cigarette (e-cigarette), typically has a housing accommodating an electric power source (e.g. a single use or rechargeable battery, electrical plug, or other power source), and an electrically operable atomizer. The atomizer vaporizes or atomizes liquid supplied from a reservoir and provides vaporized or atomized liquid as an aerosol. Control electronics control the activation of the atomizer. In some electronic cigarettes, an airflow sensor is provided within the electronic smoking device which detects a user puffing on the device (e.g., by sensing an under-pressure or an air flow pattern through the device). The airflow sensor indicates or signals the puff to the control electronics to power up the device and generate vapor. In other e-cigarettes, a switch is used to power up the e-cigarette to generate a puff of vapor.
Atomizers in electronic smoking devices may have undesirable characteristics, such as poor atomization, large liquid drops in the final atomized vapor, nonuniform vapor caused by different sizes of liquid drops, too much moisture in the vapor, and/or poor mouthfeel, etc. Accordingly, there is a need for improved atomization in these devices.
Typically, the power supply is a disposable or rechargeable battery with working voltage decreasing over its useful life. The decreasing voltage may result in inconsistent puffs.
Moreover, the heating elements may have resistances that vary in operation due to factors, such as the amount of e-solution, the heating element contacts, and the operating temperature.
Therefore, there is a need to design a dynamic output power management unit to provide a stable output power in response to the changing capacity of the battery, and/or the changing/various resistance of the heating element.